Method of making stretchable yarn



Oct. 19, 1948. R. J. cLARKs'YoN 2,451,919

uETHoD oF MAKING STRETCHABLE YARN Filed Nov. 2s, 1947 IIH BY v Mmmmwm support and ,L thereby' formed vfrom travelling viiiemtei'i 1,9. :194e

.METHOD F MAKING s'rnETcHALE YARN Robert Lemmon, wnmsbm-o, s. c.,

United States Rubber Company,

*-UNITreoSTATES PATENT OFFICE asslgnorto New York,

N. Y., a corporation of New Jersey Application November 25, 1947, Serial No. 787,974

4 3 Claims.

' This invention relates to a n'vei method of making -stretchable yarn of the general type of yarn described 2.387.320.

The Foster patent teaches howtomake an alltextilel yarnhaving high stretch characterand 'claimed in the Foster Patent lstics, pand. by following the teachings of such patent the range 'of stretch and conti-active action of the yarn can be controlled throughout. a wide range. The yarn of-such patent is well adapted for vusej-in the manufacture fof. stretchl, ablesurgical bandages. slip covers for upholstered furniture and for otherpurposes. and as a result vthere is a growing demandl for this type of yarn.

The primary purpose-of the'present invention l istofprovide ang-inexpensive method of producing stretchable yarn' of the general type contemplated by said Foster patent; and to provide a method whereby such yarn can be produced on f well known textile machinery such asis commonl'y found in textile mills.

I.l1a.ve"found that in -orderto produce a stretchable yam ofthe general type contemplated bythe Foster' patent it is" not necessary to ...wind th'e yarn around a central core or central supporting spindle as described in said patent. but that a highly twisted and coiled yarn can be fproducedat a lower cost on the ordinary ring and produce a yarn which -i`s lessi likely to kink and snarl and will operate'satisfactorily in av loom shuttle. Y

The above and other features of the present invention will be i'urtherunderstood from thefol'- lowing description when vread in connection with accompanying drawing"" showing one good pracf tical' form of apparatus forcarrying out the present method. v In the drawing:

F1g.1 1s a'vertical sectional Vview of ring spin;

ning mechanism empio ed'toimpart tight helical coils to ahigh twist yarn'.v i Y,

Fig. 2 is a vertical sectional view of somewhat similar equipment employed to open upk and re,-

- duce the number of helicalv coils imparted to the yarn by the apparatus vof Fig. 1.

traveller type of spinningl machine with some y changes In its operation.

The spinning machine is employed' to overtwist ahighly twisted yarn so that the added twist imparted to the yarn will causait to' forni helical coils. but in orderto control 'the formation of these tous 1t is important to drawth'e yam about e a fixed -support,"as it approaches the spinning spindle. to causel the yarn to bend sharply at the prevent:- the coils being away from the spinning spindle past this support. l v The spinning. apparatus used will serve to provide the highlyl twisted yarn withaseries of helical coils, but' these coils will be closed or substanv f Vtially-closed, in. that the central 'opening of each coil will be extremely'small. A yarn that is highly twisted and is also provided with these closed helical coils rwill have high stretch' characteristics and-is well adapted for yuse as 'warp` in a woven stretchalile fabric,` but it is found dimcult to weave this yarn in a=fabric as wef'tjor filling because of it leaves the Fig. 3 is an enlarged transverse sectional view, and Fig. 4 is an enlarged sidev elevation of the helically coiled yarn produced by the apparatus of Fig. 1; and

Fig. 5 is a transverse is a side elevational thecrelaxed helically coiled yarn produced by theapparatus of Fig. 2.

The method of. the, present inventiony may be v yemployed to treat variousjtypes of yarnsuch as cotton, wool,'rayon, silk, nylon and the like, but the yarn employed should' have arelatively high twistsuch as is' frequentlyreferred to vas'a. crepe twist. The highly twisted or 'crepe twisted yarn which is designated `upon the drawing by III may be a single or plyvyarn as desired. and is shown in thedrawing asr a singleyarn.- The yarn I0 may be supplied to the 'spinningequipment shown in' Fig. 1 from any suitablesource of supply. such' as a spool or package I I which is supported in ilxed bearings so that the package may rotate as the yarn III is unwound therefrom.. i During the spinning operation the yarnV I Il isdrawni'orward from thepackage II at a controlledv speed by .the cooperating rolls I2 and` I). The lower roll I2 should be driven at a speed which bears a definite relation to the speed of thev spinning spindle Il. The roll I 3 may be free running 'and positioned to rest by gravity upon the yarn I0 to prevent slippagenbetween this yarn roll The spinning spindle I t may be of usual or presectional v'iew, and Fig.

and the power driven? may have mounted means for arresting ferred construction and is rotated by the whirl il having the driving belt i8. This spindle is rotatably supportedsby .the vraill i1. The spindle thereupon 'any desired type of is wound the yarn package rail designated by 2li bobbin il upon which' Il. The usual traversing has an opening to receive the package. I9, and upon the upper face of Vthis rail is mounted the usual spinning ring 2| upon which slides the traveler/22. Some distance above the upperI end of the spindle] il is provided the usual pigtail 4guide 2l secured to the supporting block 2l which is connected by a hinge 2l to a support 26. th'e arrangement bemgsucn that the moet swung upwardly out of the way when abobbin is to be removed from the spindle.

All of the apparatus described so far by reference numerals is or may be of well known construction and constitutes one of a number of spinning units with which the spinning frame is provided. In order to impart the desired helical coils to the yarn lli it is important to provide some form of support between the feed rolls and spindle about which the yarn I will bend sharply as it advances towards the spinning spindle. It is desirable to position thissupport some distance above and in line withthe axis of the rotating spindle i4. so that as the spindle rotates the twists it imparts tothe yarn I0 will cause the yarn to coil as shown'in Fig. 1. and these coils will travel upwardly through Athe pigtail 23 but not beyond a point defined by the position of the support just mentioned.

In practice itis found that a small tightly stretched wire-21- about vwhich the advancing yarn the travel of these coils away from, the spinning spindle. Such a wire may be stretched 'lengthwise of the spinning m'achine frame parallel to the ring rail 20 so that it lies directly above the spinning spindle I4 and some distance from the feed rolls I2 and I3. It is found desirable to make this wire 2 I as small as can be used without cutting or unduly chaflng the runningyarn lll. It is also found desirable to so position this wire that the yarn l0 will be bent sharply about the same at an acute angle, so

' that the angle formed between the v ertical por.-

tion of the yarn having the coil'C and the uncoiled portion oLthis yarn advancing to the wire from the Vfeed rolls will be slightly less than 90. Under these conditions very few coils will travel past the wire 21 towards the feed rolls i2 and. I3, and by controlling the speed of the rolls i2 and i3 relative to the spindle speed the number of helical coils formed per inch of yarn l0 can be controlled fairly accurately.

In carrying -out the present invention it is important, as above stated, that the yarn i0 have a relatively high twist, and it is also important that the spindle Il be rotated in a direction to increase the twist of the yarn to thereby cause the yarn-to coilrather than twist still further. If the yarn Iilhas what is known as a Z twistfthen the package i9 should be rotated in the direction indicated by the arrow in Fig. i to further twist this yarn and produce the helical coils C shown in Fig. l, and then wind this twisted and coiled yarn uponthe package i9,

as is usual with the ring and traveler type of spinning machine.

The operation of the apparatus shown in Fig. 1 in the manner Just described will produce the helically coiled yarn that-is shown much enlarged in Figs. 3 and 4, and it will be noted in Fig. 3

24 may be that the coil C hasno central opening or practi cally no central opening. This is due to the fact that the method of forming the helical coils herein described tends to form the vclosed coil C shown in Fig. 3 rather than the open coil C' shown iny Fig. 5. lwhen it is desired to form the open coil C? oi Fig. 5 the apparatus shown in Fig. 2 may be employed and operated in the manner which will now be described. This apparatus of Fig. 2 may for the most part be similar to that shown and described in Flg. 1.

After the package i9 of Fig. -1 has been wound to the desired size it is removed from the spindle i4 and transferred to Fig. 2 where it is desigi0 is bent forms a simple but practical nated as i9' andsupported on'a non-rotating pin or spindle 2B projecting upwardly from a' rail 29.

The yarn supplied by the package I0' of Fig. '2 and having the coils C -is drawn forward from thispackageby the feed rolls i2' and il' 'if Fig. 2, and then passes from these feed rolls inan inclined direction to the pigtail 23' and then downwardly to a traveler upon the ring 2|', and

is wound in a package 30 upoma ccp Il carriedby the spindle 32 which is rotated by the whirl I3.

l Since the purpose of the apparatus shownin v Fig."2 is to relax the coiled yarn produced by the apparatus of Fig. l, by reducing the numberl and increasing the size ofthe individual coils as indicated by C', it is important that the package 30 be rotated in the opposite direction from that of the package i0, as illustrated by -the arrows shown in Fig. 1 and Fig. 2.

The operation of the-apparatus of Fig. -2 is such that the yarn'having the tight coils C is drawn forward by the feed rolls I2' and il which are driven at a definite speed with respect to that of the spindle I2. so that this coiled yarn is not relaxed until it passes the nip of the feed rolls I2 -and il', but as yarn passes from the feed rolls to the bobbin Il the coils become larger in size and fewer in number. due to the rotation of the spindle 32 in the direction to remove a substantial percentage of such coils. This direction of rotation serves also to open up the coils to increase their outside diameter and the size of the central opening as shown in Fig. 5.

It is desired to point out that the present method which utilizes an over twisting of the l yarn i0 to impart thereto the'heli-cal coils C will and that usually the stretchable yarn produced in accordance with'the 'present method will be less uniform in appearance than that shown in Figs. 4 and 6 of the drawing which show a better than average run. It is found in practice that the relaxed yarn of Figs. 5 and 6 is much easier to handle without kinking and snarling than is the tightly coiled yarn of Figs. 3 and 4.

The tightly coiled yarn of Figs. 3 and 4 can bel used as warp yarn in a fabric without serious difficulties due to snarling, since warp yarns can be maintained under sufficient tension during the weaving operation to hold them straight. This however is not the case with weft or illiing, as it isv practically impossible to maintain uniform tension upon a weft yarn as it is carried back and forth across the looms in a shuttle. It

as an elastic warp yarn and the less highly coiled yarn of Fig. 6 may be regarded as an elastic weft yarn. The relaxed yarn vof Fig. 6 will have a softer feel than that of Fig. 4.

The abilityof the yarn of Fig. 6 to contract in a fabric to impartelastic properties to "the same will be considerably lessl than that of the yarn of Fig. 4, but thi-s difference in contractive force can be taken care oi by using a higher number oi the yarns of Fig. 6 than of the yarns oi' Fig. 4. Foi-example in weaving a two-way stretch fabric in which elastic properties are imparte-d to the fabric by the yarn herein disclosed, it may be desirable to use one elastic yarn such as shown in Fie. i for each two ordinary yarns in the warp of the fabric, whereas the weit oi' the iabric may be formed entirely oi the yarn shown in Fig. 6.

In order that a further understanding o! the yarn herein Vshown and described may be had the following table is elven of a single cotton yarn, the readings shown being the averages of a number of readings: l

Properties of yarn before culling: Count.

9.2s-Z; T. P. I., 20.6; diameter, .0099".

.lifter coiling Percentage elongation at break, 86.9%.

Stress to break yarn, between 3D0-400 grams.

(Yarn did not straighten out completely before breaking).

lifter relaxing Manuiacturing turns per inch, l0.2l-1S.

Coils per inch after shrinking (l2 @ram contact load) 17.21. Outside diameter of coils, .6271". Percentage elongation when straightened, 35.4%. Stress to straighten out yarn, 360 ara. Percentage elongation at break, cl2 Stress to break yarn, 'between 40u-606 grama.

lire@ nieuwe rem im or une neuen out im a z o one. v

sired elastic properties can be imparted to the fabric by wetting the fabric and then drying it free of tension.

Having` thus described my invention, what l claim and desire to protectby Letters Patent is:

1. The method of producing an all textile stretchable yarn having controlled stretch properties, which includes the steps of drawing a crepe twist yarn about a' support so that it bends sharply about the support and then advancingit to c. revolving spindle that further twists the yarn and forms Isuccessive coils between this spindle and support. .then advancing this twisted and coiled yarn a second time and twisting it in the opposite direction to increase the diameter and decrease the `number of the coils to make the yam easier to stretch.

2. The method of producing an al1 textile stretchable yarn having controlled stretch properties, which includes the steps 0f drawing a crepe twist yarn about a support so that it bends sharply at an acute angle about the support and then advancing it to a revolving spindle that further twists the yarn and forms numerous coils between the support and spindie, then advancing this twisted and coiled yarn a second time and twisting it in the opposite direction to thereby increase the diameter of the coils and decrease their less lilrely to lrinlt. v l

noemt' r. Ginori.

nnrnnnnons nn The following rei'erences are oi' record in the file of this patent:l

. UNITED STATES PATENTS Holt NOV. 22, 1932 

